import React, { Component } from 'react'

export class Footer extends Component {

    handleCheckAll = (event) => {
        const {handleCheckAll} = this.props;
        handleCheckAll(event.target.checked);
    }

    hanldClearAllDone = () => {
        this.props.hanldClearAllDone();
    }

    render() {
        const {todos} = this.props;

        const total = todos.length;

        const doneCount = todos.reduce((pre,current)=>{
            return pre + (current.done ? 1 : 0)
        },0);

        

        return (
            <div className="todo-footer">
                <label>
                <input type="checkbox" checked={doneCount == total  && doneCount!=0 ? true : false} onChange={this.handleCheckAll}/>
                </label>
                <span>
                <span>已完成{doneCount}</span> / 全部{total}
                </span>
                <button onClick={this.hanldClearAllDone} className="btn btn-danger">清除已完成任务</button>
            </div>
        )
    }
}
